1. Field of the Invention
This invention relates to the field of instant messaging systems.
2. Description of the Related Art
Email is currently one of the most pervasive methods of communication in the world. Used for business or pleasure, email has revolutionized how companies do business and how friends stay in touch. Unfortunately, with the good also comes the bad. Electronic junk mail, known as “spam” is a term used to describe unsolicited and possibly illicit material coming from an unknown sender. The problem of spam is of such magnitude that federal legislation has been proposed and/or adopted to try to combat spam.
Another form of electronic communication, instant messaging (“IM”) is following in the steps of email as a major form of electronic communication, both for business or pleasure. Spammers of course, have moved into IM as another source of contacts to whom they can send unsolicited spam. The process of spamming through an instant messaging system has been dubbed “spimming” by, among others, Information Week Magazine. Like spam, spim is annoying to, and may even cost, IM users.
To utilize spim, a spimmer must establish a “screen name” (SN) for the system on which they intend to send spim. The current practice of instant messaging companies when setting up a screen name for a user involves the gathering of limited information, typically only a name and email address. All of the information provided by the potential user can be invalid (fake), except for the email address. The email address given must be valid because a temporary password is mailed to the given email address. The following scenario is typical:
1. Spimmer obtains an email address from an ISP or another company providing free, web-based email accounts (e.g., Hotmail, Yahoo, etc.).
2. Using the email address, the spimmer requests an IM screen name from the IM Provider (possibly the same vendor as the ISP, e.g., Yahoo).
3. The IM Provider approves the requested screen name and sends a default password to the spimmer at the email address provided during the registration process.
4. The spimmer starts sending unsolicited mass IM messages (spim) using the new screen name.
All major IM companies give users of their system the ability to block messages coming from unknown senders or specific senders designated by the user. The user may select an option whereby any messages from a screen name not contained in the user's “Buddy List” (a list of screen names with whom the user corresponds) will be automatically blocked, or authorization may be requested before the message is accepted. In addition, most IM companies allow the user to designate specific screen names and place them in an “excluded list”. Messages from screen names in the excluded list will be blocked unless they are removed from the excluded list.
A problem with this approach to blocking unwanted instant messages is that, in view of the simple manner in which screen names are obtainable, spimmers can and do have multiple screen names used for spimming. Thus, an IM user who blocks a particular screen name and any messages coming therefrom is still subject to attack by the same spimmer using a different screen name. This method requires that the user constantly update his or her list of excluded screen names as they occur. This is time consuming and annoying for IM users and is a significant problem.